[turbofan] Combine JSToNumber and ChangeTaggedToFloat64 for fast SMI case.

src/compiler/change-lowering.h

Index: src/compiler/change-lowering.h
diff --git a/src/compiler/change-lowering.h b/src/compiler/change-lowering.h
index 5d7ab41b833119f66c225bfff4723d55185909d6..6911af5b3bdf670895b233cefcd1fc66b8ddd597 100644
--- a/src/compiler/change-lowering.h
+++ b/src/compiler/change-lowering.h
@@ -31,16 +31,23 @@ class ChangeLowering FINAL : public Reducer {
   Node* SmiShiftBitsConstant();
 
   Node* AllocateHeapNumberWithValue(Node* value, Node* control);
+  Node* ChangeInt32ToFloat64(Node* value);
+  Node* ChangeSmiToFloat64(Node* value);
   Node* ChangeSmiToInt32(Node* value);
+  Node* ChangeUint32ToFloat64(Node* value);
+  Node* ChangeUint32ToSmi(Node* value);
   Node* LoadHeapNumberValue(Node* value, Node* control);
+  Node* TestNotSmi(Node* value);
+  Node* Uint32LessThanOrEqual(Node* lhs, Node* rhs);
 
-  Reduction ChangeBitToBool(Node* val, Node* control);
-  Reduction ChangeBoolToBit(Node* val);
-  Reduction ChangeFloat64ToTagged(Node* val, Node* control);
-  Reduction ChangeInt32ToTagged(Node* val, Node* control);
-  Reduction ChangeTaggedToFloat64(Node* val, Node* control);
-  Reduction ChangeTaggedToUI32(Node* val, Node* control, Signedness signedness);
-  Reduction ChangeUint32ToTagged(Node* val, Node* control);
+  Reduction ChangeBitToBool(Node* value, Node* control);
+  Reduction ChangeBoolToBit(Node* value);
+  Reduction ChangeFloat64ToTagged(Node* value, Node* control);
+  Reduction ChangeInt32ToTagged(Node* value, Node* control);
+  Reduction ChangeTaggedToFloat64(Node* value, Node* control);
+  Reduction ChangeTaggedToUI32(Node* value, Node* control,
+                               Signedness signedness);
+  Reduction ChangeUint32ToTagged(Node* value, Node* control);
 
   Graph* graph() const;
   Isolate* isolate() const;